Basic cellular information Flashcards
(19 cards)
Difference between eukaryotic and prokaryotic
Eukaryotic: Animal cells, consist of an enclosed cell membrane and enclose nucleus, have membranous bound organelles, surrounded by cytoplasm cytoskeleton.
Prokaryotic: Bacterial cells, consist of cell wall, lack nucleus and membranous cytoplasmic structures.
Blastomeres
1st zygotic cells produced. Give rise to all tissue types in a fetus.
Plasmalemma (Plasma membrane)
Cell membrane of all eukaryotic cells. Consists of:
- phospholipids
- cholesterol
- oligosaccharides
- proteins
The fluid mosaic model
Cellular membranes are comprised of different molecules that are scattered about in a mosaic pattern. These molecules are always moving within the membrane, hence its fluidity.
Diffusion
Energy independent method that transports small, non polar molecules directly though the lipid bilayer.
Channels
Proteins that allow ions our small molecules to pass through the bilayer selectively. Are energy independent and rely on gradients.
- Water uses specialized channel proteins called aquaporins.
Carriers/pumps
Proteins that bind small molecules and transport them across the lipid bilayer via energy use (ATP).
Endocrine signaling
Endocrine glands signal to cells far away through the use of hormones and the bloodstream.
Paracrine signaling
Local cells signal to other local cells from close distance via diffusing chemical ligand into the extra cellular fluid. Ligand rapidly degrade.
Synaptic signaling
Special kind of paracrine signaling in that one cell communicates with adjacent cells via synaptic contact and neurotransmitters.
Autocrine signaling
Cell communicates with itself (increase or decrease the magnitude of an action) by binding the chemical signal to its own receptors.
Juxtacrine signaling
Cells communicate with one another via direct physical surface binding.
Channel-linked receptors
Transfers molecules or ions across a membrane when a specific ligand binds to the receptors.
Enzymatic receptors
Produces catalytic activity within the cell when a specific ligand binds to the receptors.
G-protein-coupled receptors
Stimulates associated G-proteins which then release GTP to activate other proteins when bound to a specific ligand.
Lipid rafts
Areas of the lipid bilayer that are heavily condensed with cholesterol.
-prevent movement within the fluid bilayer.
Concentric muscle movement
Initiate movement
Eccentric muscle movement
Resist movement
Isomeric contractions
Maintain position
